Comparing mechanism



y 1950 F. c. HALLDEN 2,514,054

COMPARING MECHANISM Filed May 6, 1948 3 Sheets-Sheet 1 Deg/555, 0 36 72 I03 M4 /80 2/6 252 286 324 360 C B 5 ,b/"i

I INVENTOR CARD FEED-CL arc/45s ENGAGE-+ FRED C HALLDEN AGENT y 1950 F. c. HALLDEN 2,514,054

COMPARING MECHANISM Filed May 6, 1948 3 Sheets-Sheet 2 INVENTOR FRED C. HALLDE/V AGENT July 4, 1950 F. c. HALLD'EN COMPARING MECHANISM 3 Sheets-Sheet 3 Filed May 6, 1948 mm mm bw 0m mm mm INVENTOR FRED c HALLDEN a 5am AGENT Patented July 4, 1950 UNITED STATES PATENT OFFICE COMPARING MECHANISM Application May 6, 1948, Serial No. 25,500

8 Claims.

This invention relates to apparatus for storing and comparing electrical impulses by the medium of small fixed capacitors.

More particularly the present invention is directed to electromechanical devices for the storage and comparison of record card data in an electrical accounting machine of the type illustrated in U. S. Patent 2,359,670. The features of this invention, however, are not limited to electrical accounting machines, but may be applied to any electrical apparatus wherein the storing, comparing, and selecting of electrical impulses are required.

Briefly the subject invention comprises a rotating element containing a plurality of pairs of small fixed capacitors arranged to be charged and discharged by means of contact brushes and contact segments to which the capacitors are connected. In the embodiment chosen the element is rotated in timed sequence with the feeding of a record card having perforations which pass under electrical sensing stations as the card is fed. Electrical circuits are provided from the sensing stations to energize gas triodes, which become con ductive, providing a potential drop for charging selected capacitors in the rotating element by suitable connections to the contact brushes. Thereafter the charges on the capacitors are delivered to electronic comparin circuits through other contact brushes associated with the rotating elements. Provision is also made by means of another set of contact brushes coacting with the rotating element to recharge a capacitor regeneratively; for example, when a gas triode is not energized by a sensing station, the energization being provided by sensing the charge remaining on the capacitor which is to be regenerated. Regeneration of a chargein this manner may be produced periodicall for an indefinite length of time to effect a perpetual type of impulse storage in a fixed capacitor having normal leakage resistance.

The principal object of this invention is therefore to provide a perpetual capacitor storage device for electrical charges.

Another object of this invention is to provide a novel electronic comparing circuit energized from electrical potentials derived from charges stored in small fixed capacitors.

Still another object of the invention is to provide a condenser charging and discharging device wherein charges upon small capacitors are utilized to control gas triodes to regeneratively charge the capacitors.

A further object of the invention is to provide a 2 invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is a sectional view of a capacitor electrical storage unit.

Fig. 2 is a sectional view of a socket and drive into which the storage unit of Fig. l is plugged.

Fig. 3 is a diagrammatic view of the storage unit of Fig. 1 showing the various sets of contact brushes.

Fig. 4 is a fragmentary circuit diagram and diagrammatic view of a storage unit illustrating the principle by which the fixed capacitors may be charged from data sensed in perforated rec- 0rd cards.

Fig. 5 is a fragmentary circuit diagram and a diagrammatic view of a storage unit illustrating the manner in which the fixed capacitors are charged (and regeneratively recharged) in the present invention.

Fig. 6 shows a fragmentary electrical circuit adapted to comparing charges upon a pair of capacitors in the storage unit.

Fig. 7 is a fragmentary circuit diagram of a selector circuit utilized in the subject invention.

Fig. 8 is a circuit diagram illustrating the present invention as it might be embodied in a machine of the type described in U. S. Patent 2,359,670.

Fig. 9 is a timing chart relative to the circuit diagram of Fig. 8.

Referrin now to Fig. 1, a c lindrical base ll composed of insulating material, contains a central bearing l2, the base being surmounted by a cup l3 having a bearing 14. A cylinder l5 of insulating material is fixed to a shaft 16 supported freely by the bearings 12 and I4 and having a driving end l1. Within the cylinder it? are contained a plurality of small fixed condensers 18, there being a total of twenty such capacitors uniformly distributed in pairs throughout the cylinder i5. Each pair of condensers It is connected in series with their connections being led to contact segments l9 imbedded and spaced uniformly in the lateral surface of the cylinder i5 in groups of threes. The outer segments I9 each connect with a condenser E8 of a pair having a common connection to the center segment ii! of the group.

A brush holder 20 forms a raised part upon the base II and carries three (3) sets of contact brushes 2| which ride upon the surface of the cylinder it making contact with their respective segments l9 as the cylinder I5 is rotated. With reference also to Fig. 3, for purposes of clarity these sets of brushes are defined as set K having three (3) brushes, set L having three (3) brushes, and set M having two (2) brushes, the brush normally contacting the center segment 19 being omitted in set M. Each brush is connected by a wire such as 22 to a contact pin 23 projecting 3 through the base I I, there being a total of eight (8) such pins corresponding to an equal number of brushes 2|.

The unit shown in Fig. 1 is pluggable into a socket as shown in Fig. 2, the socket comprising an insulated receptacle 24 having eight (8) pin sockets 25 for connecting with the pins 23'. The receptacle 2 3 also has a keyedsocket 26 connected to a drive shaft 21 which may be driven through any conventional means. with the end ll of the shaft l6, thereby affording a means to rotate the cylinder [5.

Now referring to Fig. 4, an electric circuit is.

shown wherein the condensers H8 in a storage unit similar to that of Fig. 1 are charged by voltage impulses derived from conventional card Sensing stations. A sensing station A, comprising a contact roll 28 and a sensing, brush 29, connected as shown, is arranged to have a record card 30 fed to it so that a perforation representing certain data may be sensed in a manner well known in electrical accounting machines. A similar sensingstation B, comprising a contact roll 3! and a sensing brush 32, connected as shown, is arranged to. sense a record card 33. The cards 30 and 33 are fed in synchronism with the rotation of the cylinder I5 so that correspondingly indexed positions in the cards coincide with positions of the cylinder 15. Let it be assumed that a perforation occurs at the i index position of card 30 and a perforation occurs at the 2 index position of card 33. When the 4 perforation in card 30 is sensed at sensing station A a circuit is completed from a battery 3'4 to the central brush 2th, through a segment id, to the common connection of the pair of condensers i8 (corresponding to the 4 position of cylinder i5) through the condenser i812 (left side of cylinder l5, see Fig. 4) to a segment l9 (left side), through a brush 2 lo (left side), to brush 29, contact roll 28, to grounded side of battery 3Q, thereby charging the condenser 18b (left side). When the 2 perforation in card 33 is sensed at station B a similar circuit is completed via brush 32 and brush Zia to charge a condenser i817. (right side of cylinder i5, see. Fig. 4) Any condenser l8in the cylinder I5.may be charged in the manner described, the charge normally remaining thereon for a time dependent upon its leakage resistance.

In the presentinvention it has been found to be more practicable to charge the condensers i8 by means of a circuit illustrated inFig. .5, certain advantages being obtained thereby. Let the brushes. 2.!a, 21b, and Zic representthe. set of brushes L (Fig. 3), the brushes 21g and 24h represent the set M (Fig. 3), and the brushes Eli, M8, and Mt represent the set of brushesv K (Fig. 3). A plug hub P--l is plugged to the sensing brush (e. g. the brush 32 of Fig. 4) ofa. conventional record card sensing station. such asB of Fig. 4 so that a positive voltage impulse is delivered to P! when a perforation in a record card is sensed. When charging a condenser I8 (as in preceding paragraph) a switch S-l is thrown to its top contact so that a positive voltage pulse is delivered to the grid of a gas triode G-| when a perforation occurs in the card. The triode Gi is connected across a direct current source having a positive line WI and a negative line W-2; consequently, G--l becomes conductive and current flows through a resistor R! provided that a circuit breaker CB-ll is closed. Azvoltage drop is thereby developed by the resistor R-i which is provided by connections (as shown in Fig. 5) across the brushes Zla and 21b to cor- The socket-26 engages responding segments IQ of the cylinder i5 as it turns on shaft It to charge a condenser (e. g. a condenser i8 of Fig. 4) having its terminals connected to the corresponding segments i9.

Normally the circuit breaker CBB is closed for a period from the time a group of segments i9 passes under the set of brushes K (see Fig. 3 also) until the same group of segments passes out from under the set of brushes L. The brush sets K and L, accordingly, are spaced to have the distance between their respective points of contact with cylinder it less than the distance between two adjacent groups of segments E9 on the cylinder i5. While switch Si remains on its upper contact, if no positive voltage impulse is received at the plug. hub Pi the gas triode G-l remains non-conductive, and, as the cylinder i5 rotates, the segments i9 pass under the brushes Ziaand Zib thereby discharging each charged condenser is through the resistance R-i.

The polarity of the voltage (derived from the drop across Ri) providing the charging current for a condenser i8 is such that a segment i9 passing under brush am is positive and a segment 19 passing under brush 2!?) is negative. When the switch S--i is thrown to its lower contact, as the cylinder it rotates, any charged condenser [8 having its terminals connected to corresponding segments i9 is sensed by the brushes 2H1 and 2ls, and a potential is thereby provided across the grid-cathode circuit of the triode G-l, rendering G-l conductive provided the potential is sufficient in magnitude. Consequently when a charged condenser 18 passes under the brushes 2lr and Zis in this manner, Gi conducts and remains conductive until 013-4) opens the circuit. Hence a voltage drop is set up across resistor R-i until the segments it connected to the condenser it pass under the brushes 25a and 2lb at which time the voltage drop is applied across the condenser E8 to recharge it. In the manner just described the charge upon any condenser l8 may be regenerated again and again as the cylinder 15 rotates to provide a voltage impulse storage means of indefinite duration.

Referring now to Fig. 6, it is obvious that circuits and energizing means suitable for charging both the condenser ifla and the condenser i811 can be provided as previously explained. The brushes 21g and 2 Hz (brush set M of Figs. 3 and 5') are spaced from the brush set L a distance equivalent to the distance between two adjacent groups of segments IQ of the cylinder 55 so that after the condensers We and I8?) are charged they are presented one cycle point later to the brushes Big and 2H2 as the cylinder I5 is rotated. The circuit shown in Fig. 6 enables the status of charges upon the condensers to be determined. A pair of gas triodes G2 and G-3 are connected with their cathodes in common through a resistor R.? to a conductor W3 representing the negative side of a direct current source. The anodes of the gas triodes G2 and G--3 are connected respectively through a pair of resistors R-3 and R 1 to a conductor W4 representing the positive side of the direct current source. lhe grid of G2 is connected to brush 2H1. and the grid of G-3 is connected to brush 2| g, there being also connections from the grids respectively through the resistors R--5 and R% to the conductor W-S.

Let it be assumed that condenser iBa alone is charged. When segments 59 contact the brushes Zig and 2th the condenser 180. will discharge causing a current to flow via brush 2Ig, resistor lit-6, resistor R-5, brush Zlh, and condenser l8b. A voltage drop will be set up in resistor R-fi raising the potential of the grid of G--3 and in resistor R5 lowering the potential of the grid of G--2, each with respect to its cathode. The triode G-3 therefore becomes conductive and a current flows from W4, through R-4, anode and cathode of G3, R-8, R2, to W3. The voltage drop produced in R2 thereby provides a negative bias to the grid of G-Z via the resistors R5 and Rl, sumciently greater than the positive potential derived from condenser |8b in the event that such potential is applied while G3 is conductin to retain G-Z non-conductive. A correlative condition prevails when the condenser 1827 alone is charged.

When neither condenser [8a nor condenser l 8b is charged it is obvious that no voltage drop is set up in either R-5 or R-fi to render either G--2 or G3 conductive. Similarly when both condensers lac and I819 are charged to the same potential there will be no difference in potential between brush 2 lg and brush 2 H7. and no current will ilow through R5 and R-6 so no voltage drop is provided to render either G2 or (3-3 conductive. When G2 becomes conductive the potential of a terminal TI rises, and when (3-3 conducts the potential of a terminal T-2 rises; consequently, another electronics circuit may be controlled thereby to utilizethe features oi the circuit shown in Fig. 6.

For purposes of illustration, let it be assumed that two storage units, each with an associated circuit as in Fig. 6, are employed, as for example in a record controlled machine where for control purposes the data read from one column of a record card is to be given preponderance over data read from another column. Fig. 7 illustrates a selector circuit utilized in the present invention wherein a selector disc 35 has a pair of brushes 36 and 3'5 sweeping respectively over contacts Vl, V-3 and V2, V4. Let it be assumed also that circuit connections are provided from T--l (Fig. 6) to Vl, from T2 (Fig. 6) to V2, and similar connections from the second storage unit circuit mentioned above to V3 and V4. The brushes 36 and 31 are connected respectively to the grids of two as triodes C--4 and G-5 having their cathodes connected in common through. a resistor R-9 to the conductor W-3 and having their anodes connected respectively through the magnets M-l and M2 to the conductor W i. The comparing circuit connected with contacts V! and V2 will have preponderance for control over that connected with V-3 and V4. Assume, as has been previously explained, that the potential of Tl (Fig.

6) has risen so that Vl is at a positive potential with respect to conductor W-3 and that V2 is neutral while V-3 is neutral and V4 is at a positive potential. When the brushes 36 and 37 encounter V-l and V2 respectively the gas triode G4 will become conductive, current will flow from W4, through Ml, G4, and R-9 to the conductor W-3. A voltage drop will thereby be set up in R-9 to bias the grids of G4 and (3-5 so that neither will thereafter be capable of being rendered conductive .by positive potentials derived by the brushes 36 and 31 as they sweep over the contacts V-3 and V-4 respectively. G4 remain conductive, however, until its anode circuit is interrupted and the preponderance sought is accomplished. When energized the magnets M-i may be used to control theoperation of arec'ord card machine-inane manner and M2 in an opposite manner, e. g. to feed primary cards or to feed secondary cards. When both V-| and V2 are neutral, indicating no desire therefrom for control, the preponderance for control is shifted to VS and V4, either of which, if positive, will render G-4 or G-S conductive. In this manner any number of positions may be selected for control preponderance merely by adding additional contacts upon the selector disc 35 and connectin these with additional storage units having comparing circuits as already explained.

Having now described the essential features of the invention, a complete embodiment is shown in the circuit diagram of Fig. 8 as applied to a record controlled or the type commonly referred to as a collator. Essentially in its simplest form the collator compares record cards of two classes; namely, primary cards and secondary cards, feeding record cards of one clas ahead of cards of the other class in order of their corresponding data designations. Many other functions are performed by record controlled machines Of this type, see for example U. S. Patents 2,359,670 and 2,379,828, but for purposes of illustrating the utility of the present invention it will suffice to explain the operation of the present invention only to the extent where a primar card may be said to be higher, lower, or equal in denomination as compared with a secondar card. In the embodiment illustrated (see Fig. 8) this distinction will be evinced by the controlling of certain contacts; namely, RL-Sa and RL-4a (Fig. 8), to complete a circuit to one cf the three terminals LS, LP, or EQ (Fig. 8), these corresponding, respectively, to the three connection shown leading from the contact strips 412 and 413 and the extreme right contact strip 416 of the Secondary Comparing Unit of Fig. 17a, U. S. Patent 2,359,670.

Referring now to Fig. 8, provision is made for comparing record cards wherein more than a single column 01"; data in each card is compared at one time, there being two combined units shown, each comprising a storage unit, a regenerative capacitor charging circuit, and a comparing circuit. It is obvious that the capabilities of the present invention may be expanded by including as many of these combined units as are desired. Each combined unit includes a storage unit (partially shown in Fig. 8 by dotted lines) having a cylinder 15a or iiib provided with condensers l8 arranged in pairs, their terminals connected with the segments l8. Coacting with one of these storage units are three sets of brushes, the sensing brushes 38, 39, 40; and charging brushes 4|, 42, 43; and the comparing brushes 44 and 45. The first two brush sets mentioned are connected with a pair of gas triodes (Ii-25 and G! having as circuit components the resistors R.-l0, R-H, it-42, Fir-l3, R-M and Rr!5, the relay contacts RLla and BL-2a. and the plug hubs U-l and U2. lhe third set of brushes is connected with a pair of gas triodes G-l0 and G--ll having as circuit components the resistors R-lfi, R-l'l, Rfi-ifl, R-IQ, and R-20. Coacting with the other of the storage units are three sets of brushes, the sensing brushes 46, 41, 48; the charging brushes do. 50, 5|; and the comparing brushes 52 and 53. The first two sets of these brushes are connected with a pair of gas triodes G8 and G9 having as circuit components the resistors R2l, lit-22, R23, R24, R25 and R2S, the relay'contacts RLlb and RIP-2b, and theplug hubs U-.3

and TI -4. Thethird set of brushes is connected:

with a pair of. gas triodes GiE and GI- i having as circuit components the resistors R-2T, R-28, ft-29, R30, and R-3l. The cathodes of G -H and Gld are connected, respectively, to a pair of inserts to and '6! on a selector disc SD, and the cathodes of (Ii-I3 are GI Z are connected, respectively, to a pair of inserts 52 and 53' on the selector disc SD. A pair of contact rings 55 and 51 are provided on the disc SD upon which a pair of sliding contact brushes 58 and 59, respectively, slide. These brushes make contact with the said inserts as they are revolved together upon their respective rings, the brush 58 operating to connect the inserts to and 62 to the ring 56 and the brush 59 to connect the inserts 6i and 63 to the ring 51. For each combined unit added, similar to that representing column #1 or column #2 of Fig. 8, an additional pair of inserts is'added to the disc SD. The rings 56 and are connected to a pair of gas triodes G-l4 and GIE, respectively, which have circuit components comprising resistors R-32, R'33, R-Sd, R-35, and R-35, the biasing batteriesEC-2 and EC-3, and the relay coils RL-3 and RIP-4'. A pair of conventional contact rolls CRP and CBS similar to PCB! and SCR of Fig. 35, U. S. Patent 2,359,670 are provided having respectively the common brushes 5d and '55 which are connected to the positive line W4 of a direct current source through a circuit breaker (EB-4'. Another circuit breaker CB-Z connects the anodes of the gas triodes G5, Gl, GB, and G-9 with line W l, and a circuit breaker CB- 3 connects the-anodes of gas triodes GHJ, Gl l, G--l2 and 6-43 with the positive line W'4. Gas triodes Gld and Gl5 have their anodes supplied from the positive line W-' l via a circuit breaker (IE-41. Negative bias is supplied to the grids of the gas triodes GS, GI, G8, GQ, Git, G---! l, GiZ, and Gl3 by a batteryEC-l having its positive terminal connected to the negative line W3 of the direct current source, and. the grid of triode Gld is biased by a battery EC-Z-l and the grid of G l5 by abattery EC2, these batteries being connected respectively through the resistors R-t and R35 to the negative line W'--3.

A circuit breaker CB-5 is also connected with line W-4 to the relay contacts RL-3a and RIP-4a to supply the terminals LP, LS, and EQ. A timing chart for the various circuit breakers is shown in Fig. 9. It is to be noted that the brushes 58 and 59 make one complete revolution of the selector disc SD at the end of each cycle, andwith respect to Fig. 9, this must occur when thecircuit breaker 'CB- i is closed.

Associated with the contact roll CRP are a group of sensing brushes 64 each connected to a plub hub P6, P1, P8, or P9, and with contact roll CBS 2. group of brushes 85 each connected to a hub S6, S1, S8, or S9. Perforated record cards are fed between the brushes 54 and contact roll CRP and between the brushes65 and contactroll CRS by card feed means (not shown) similar to that shown in Fig. 3b of U. S. Patent 2,359,670. Cards are fed in synchronism to each of the contact rolls so that corresponding card index positions arrive under the brushes $4 and 65 in time relation with the making of the CB-l contacts. A circuit breaker PRI-l operates with the card feed feeding a card to the contact roll CRP toenergize a relay coil RL-l, and a circuit breaker SEC-l operates with the card feed feedingacard to the contact roll CRS to energize a 8 relay coil RL2. The timing of PRI -l and- SEC-1 is also shown in the timing chart of Fig. 9; it is to be noted, however, that these circuit breakers operate only when their respective card-feeds operate while the other circuit breakers*(-CB--'l to 03-5) are operating continuously.

The storage unit, previously discussed, is shown partially (see dotted lines of Fig. 8), a partial development of the cylinder [5 being shown, together with some of the condensers I8 and their contact segments IS] in each of the combined units (shown as I50 for column #1 and as 15b for column #2). Each cylinder I5 is arranged to revolve so that a group of segments [9 arrives under the brush station formed by the brushes 4|, 42, 43 (or the brushes 49, 55, 5|) during each time the contacts of circuit breaker CB -Z are made.

It is to be noted therefore that a record card is fed during the first degrees of the operation cycle, that each storage unit cylinder makes two complete revolutions each operation cycle, and that the selector brushes make one complete revolution during the second half of each operation cycle.

In order to more clearly understand the utility of the invention as embodied in the circuit of Fig. 8, let it be assumed that plug wires are connected:

(a) From hub U--l to hub P--B (b) From hub U-2 to hub S6 (0) From hub U-3 to hub P-'| (d) From hub U-4 to hub 8-! Also let it be assumed that record cards are fed to the contact rollsCRP and CBS, the cards each containing perforations representing data in two of the card columns, respectively sensed by the brushes 64 connected to hubs P6 and P1 and by the brushes 65 connected to hubs S6 and S1. The cards are fed with their highest numerical designation leading. Let it be further assumed that perforations sensed by the brushes connected to P6 and S6 represent the tens order and those sensed by the brushes connected to Pi and S! the units order, i. 'e. corresponding respectively to column #1 and column #2 (Fig. 8).

Assume the card fed to CRP is perforated to represent a numerical value of 21, i. e. perforated at the 2 index position in the tens column and at the 7 index position in the units column, and the: card fed to CBS is perforated to represent anumerical value of 22 in a similar manner. The record cards being fed with perforations representing the highest values leading, the first designation sensed is at the '7 index position of the card being fed over contact roll CRP, which places a positive charge on the grid of G8 via line W4, CB-l, brush 54, contact roll CRP, brush 64 leading to plughub Pl, plug wire to plug hubU-3, resistor R25, contact R.Llb (transferred since RL- -l is energized due to PRI-l contacts being made whenever the card feed to CRP operates). GB therefore becomes conductive, and a circuit is completed from W-4, via CB2, anode of G8, cathode of G8, 'R-2'3, line W3a, to line W-3, and a voltage drop is produced in resistor R-23. As the cylinder l5b pertaining to the storage unit associated with G8 isrevolving a condenser [8 will be chargedwhen its segments [9 pass under the brushes 49 and :55 due to the voltage drop in R-23. The companion condenser 18 having its segments IS 'under the brushes 56 and M will not be charged at this time since there is no voltage 9 drop in the resistor R-M, G-9 not being conductive.

The card fed to CRP is fed simultaneously with the card fed to CBS, so that when the cards advance to have their 2 index positions under the brushes 64 and 55 respectively, positive pulses are supplied to the grids of G-6, G-l and G--9 in a manner similar to that already described. With respect to G--9, when a positive pulse is supplied, G9 becomes conductive and a circuit is established from W-4, via CB2, anode of G-Q, cathode of G--9, resistor Rr'24, W3a, to W-S, and a voltage drop is produced in resistor lit-24. Hence a condenser l8 of cylinder lb whose segments is fall under the brushes 50 and 5| will be charged by the voltage drop in resistor R-24 at this time.

Since the cylinder l5b is revolving, it is obvious that the condenser 18 charged by resistor R.23 and its uncharged companion condenser will advance so that their segments 19 pass under the brushe 52 and 53 before the segments is associated with the condenser l8 charged by Elf-2 5. Consequently, due to the discharge of the con denser l8 through the circuit brush 52, resistor R-3l, resistor R-38, brush 53, a voltage drop will be produced in resistor R3| to swing the grid of G-iZ positive causing G--l2 to conduct. A current will thereby flow from W- 4, via CB--3, line W1, anode of G-l2, cathode of G-l2, resistor R-ZI, resistor R,29, to line W-3. The voltage drop in the resistor R29, thereby produced, will bias the grids of Ci -l2 and G-l3 sufiiciently to prevent a charge of another charged condenser [8 from rendering either (3-! 2 or G-l3 conductive. Unlike CB-i, which is timed to break its contacts between each passage of a group of segments I 9 under the brushes 49, 5B, 5!, the circuit breaker CB-S retains it contacts closed continuously for 2'70 degrees of the operation cycle (see Fig. 9). (3-!2 therefore remains conductive, but G-I3 remains non-conductive and is unaffected by the passing under the brushes 52 and 53 of the segments I9 associated with the condenser l8 charged by resistor R-24.

With respect to G--6 and G-l, each receives a positive pulse upon its grid simultaneously, each thereby being rendered conductive at the same time, and both condensers l8 of a pair conse quently being charged simultaneously when their segments it pass under the brushes M, 43. Therefore when the cylinder l5a revolves and the condensers l8 have their segments iii pass under the brushes M and 45, no potential difference is provided across resistors R-ll and B 2!) so that neither G-I!) nor G-ll becomes conductive. Since neither Gl0 nor G-ll con ductive there will be zero voltage drop across the respective resistors R-IS, R-l'i, and lk-2%, and the potentials of the cathodes of G l 6-! l with respect to line W3 will be Zero. 0n the other hand the potential of the cathode of G-! 2 with respect to W3 will be the sum of the voltage drops in resistors R-Z'! and Rr2fi while the cathode potential of G-JB will be equal to the voltage drop of resistor l te-29.

When the brushes 58 and 59 sweep over the selector disc SD during the second half of each operation cycle encountering the inserts i313 iii no change of potential occurs at the grids of Gl4 or (Bi-l5. When the brush 58 contacts the insert 62 a positive potential equivalent to the voltage drop of resistor R,29 is applied to the grid of GI4; however, the bias battery EC-3 is suflicient to prevent the triode G-M from becoming conductive. When brush 59 encounters the insert 63, however, a positive potential equivalent to the sum of the voltage drops across R2'! and R-29 is applied to the grid of G|5 sufficient to overcome the negative bias of the battery EC-Z and render (3-! 5 conductive. The relay RL-3 is thereby energized via a circuit line W--4, CB-4, anode of G !5, cathode of (i-I5, relay ELL-3, resistor R,34, to line W-3. The relay contacts R.L-3a are thereby transferred so that when the circuit breaker (DB-5 closes its contacts a voltage pulse will be transmitted from the line W3 to the plug hub LS which is plugged to control the feed ing of cards from the contact roll CRS ahead of cards from contact roll CRP similar to a machine such as that described in U. S. Patent 2,359,670. In other words, control is provided in accordance with the order or equence of the record cards that are sensed and compared. With the arrangement shown in Fig. 8 if a higher order card were sensed at CBS than at CR1, a similar operation would be effected to operate the relay RL-4 and its contacts RL4a (transferred) to deliver a pulse via the plug hub LP. When the cards sensed at CRP and CBS are the same order, or when cards are not sensed at both CRP and CBS, no pulse i received by either G-l4 or Gl5 so that a pulse is delivered via the circuit breaker CB5 and the normally closed contacts ELF-3a and RL4a to the plug hub EQ. It is to be further noted that when either Gl i or (3-45 is conductive, the voltage drop in resistor R-3 t is added to the negative bias of the battery EC-Z or EC3 to prevent the other gas triode from responding to a pulse which might be derived from the brushes 58 or 59 contacting insert 67 or 68, respectively, the latter being at positive potentials resulting from the sensing of data in columns of the record cards representative of lower digital significance when control has already been established by a higher digital significance.

When cards are fed to and sensed at CRP and are not fed to and sensed at CR8, or vice versa, the designation of the last card so fed and sensed will prevail in the storage unit involved until further cards are fed and sensed. For example, let it be assumed that a card having a numerical designation "35 is fed to CR8 and thereafter no cards are fed to CBS although cards continuously are fed each cycle to CRP. When the card is sensed by CBS the tube G--'l will become conductive as the 3 index position is sensed and the tube C-.9 as the 5 index position is sensed. Consequently a condenser [8 in the cylinder [5a of the associated storage unit will be charged as the cylinder rotates to bring segment 59 under the brushes 2 and as via the voltage drop in resistor Rl3 (in a manner similar to that previously described). Since the charged condenser l8 advances as the cylinder l5a revolves, the charge on the condenser will be sensed by the comparing brushes 44 and 45 to actuate the tube G-ll so that comparing is made with pulses supplied to Glil, as previously described. While cards continue to be fed the circuit breakers FRI-4 and SEC-l operate as shown in the timing chart (Fig. 9). When no card is fed over CBS, however, its feed clutch is not engaged at 234 degrees (see Fig. 9); consequently, the contacts of SEC-l remain open. Therefore the relay RL-2 remains de-energized and the contacts RL-2a and RL-Zb do not transfer.

G--I2 and Gl3) to conduct, a portion of the charge is drained off via the current in the resistors R-l9 and R20 v(or R'30 and R-3i). Also when one condenser .of a pair of condensers I8 is uncharged and the other charged, as their 7 segments 19 contact the brushes 44 and 65, a current through resistors R-I9 and Pia-2% will flow from the charged condenser i8 tending to charge the uncharged condenser of the pair (similarly regarding brushes 52 and 53 relative to re- .sistors R3[! and 'R-3l')'. Since the resistors RP-l9 and R-Zil (or R-.30 and R-3i) are selected to have a value of 100,000 ohms or more, and the brushes 44 and. 45 (or 52 and 53) contact the segments [9 for a relatively short in terval, the drain from the charged condenser l8 will be negligible and the extent to which the uncharged condenser of a pair of condensers I8 is charged will be very slight. Consequently the extent to which a charged. condenser i8 is discharged in this manner is immaterial.

Therefore after a charged condenser 43 passes its segments i9 under the brushes t4 and 45, its charge is substantially unafiected, and if the contacts RL2a remain in their normal posi tion (which is the case when the circuit breaker I);

.SECI is open) .a-charge will be sensed by the brushes 39 and 40 as the cylinder lea continues revolving sufiicient to render the tube Gl conductive. Consequently the condenser I8 which rendersG'l conductive will in turn be recharged the cylinder |5b with respect to the contacts RL2b and the brushes M, 48, 50, .and 5!- and the gas triode .G--9. When no cards are fed to CRPsimilar action takes place.

- When cards are fed continuously to OR? or CBS any charge remaining on any condenser is? is removed by leaking ofi over one of the resistors -R-l2, Rr-\l3, R23, or R--24 (since the contacts ferred) unless a designation is sensed at CR? or CRS which would produce an identical charge with that already on the condenser.

Since the values of some of the electrical cornponents are somewhat critical, as heretofore noted, alist of values which may beused is here inafter tabulated:

G--| to G-l5:Type 884 (RCA) gas triode Condenser l8: .1 mfd.

EC--l 25 volts D. C.

EC-2, EC3: 80 volts D. C.

Line W--3 to line W- l: 115 volts D. C.

' ohms While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from the spirit of the invention. It is the intention, therefore, to be lim ited only as indicated by the scope of the following claims.

What is claimed is: I

1. In a record controlled machine wherein record cards are fed having data, representations at index point positions, means for sensing successively the said positions, a series of capacitors including one capacitor for each "said position, a normally eifective capacitor discharging means capable of dissipating an inherent charge on any of said capacitors, a normally 'ineiiective' capacitor charging means capable of charging a said capacitor to a, predetermined value, means for moving said capacitors successively into operative relation with the said discharging means and with the said charging means concurrently with the sensing of the respective positions of record card, and means controlled. by the sensing means for rendering the said charging means effective and simultaneously rendering the said discharging means ineffective when a data repre" sentation is sensed.

2. In a record controlled-machine wherein record cards are fed having data representations at index point positions, means for sensing successively the said positions, a series of capacitors including one capacitor for each said position, an impedance, means for connecting said capacitors successively across said impedance concurrently with the sensing of the respective positions of a record card normally whereby a residual charge upon a capacitor leaks off, and means controlled by the sensing means for developing apctential across said impedance when a data 5 representation is sensed effective to charge the capacitor then connected across the said impedance.

3. In a record controlled machine for storing representations of record card data, means for successively sensing the index point positions of a record card, an electronic device rendered conductive responsive to the sensing of a data representation at one of the said positions, a plurality of capacitors one corresponding to each said position, circuit connections to the said device for deriving a potential therefrom when said device is conductive, distributing means coacting with the said connections for selectively charging a said capacitor, means for reading successively each of the said capacitors to detect a charge, and means for disconnecting the said electronic device from the said sensing means and for connecting the said detecting means thereto whereby a charged capacitor renders the said device conductive to recharge the said capacitor.

.4. In a record controlled machine wherein record cards are fed having data representations at index point positions, means for sensing successively the said positions, a series of capacitors in-- cluding one capacitor for each said position, a normally inefiective capacitor charging means capable of charging a said capacitor to a predemrmined value, means for moving the said capacitors successively into operative relation with the said charging means concurrently with the sensing of the respective positions of a record card, means controlled by the sensing means for rendering the said charging means eiiective when a data representation is sensed, means for detecting a charge upon a said capacitor, means for 13 transferring control of the said charging means from the said sensing means to the said detecting means for rendering the charging means effective when a charge upon a said capacitor is detected, and delay means for continuing the said charging means effective for a predetermined time.

5. In a comparing device for control records having data representations at index point positions, a plurality of pairs of capacitors, one pair corresponding to each said position, means for sensing concurrently like positions in two of said records, said means being arranged to sense the different positions in each record sequentially, means under control of the said sensing means for charging a related capacitor each time a data representation is sensed, means for detecting charges upon the pairs of capacitors sequentially each cycle, a pair of control devices, and means controlled by the said detecting means upon detecting the first charged capacitor of a pair in a cycle, for selectively operating one of the said control devices.

6. In a comparing device for control records having data representations at index point positions, a plurality of pairs of condensers, one pair corresponding to each said position, means to sense corresponding index point positions of two records simultaneously, the said means being adapted to sense the different positions in each record in sequence, means under control of the said sensing means for charging a related condenser each time a data representation is sensed, cylindrically operative means for detecting charges upon the pairs of condensers successively each cycle, a pair of control devices, and means controlled by the said detecting means for operating one or the other of the said control devices according to the disparity of charge detected between a pair of condensers.

7. In a comparing device for comparing two data representing means, means for sensing concurrently the two said data representing means, said sensing means sensing both data representing means sequentially over a predetermined number of different data values, two series of series of capacitors, means to bring the capaci tors of both series pertaining to each said value into operative relation with their related charging means coincident with the sensing of said data representing means for the respective data values, means controlled by the said sensing means upon the detection of a value in either ofthe said data representing means for rendering the related charging means effective, means for comparing the respective charges onpairs of corresponding capacitors in the two series pertaining to each said value, and a pair of normal 1y inoperative control devices selectively operableby the said comparing means according to the disparity of the compared charges.

8. A device for comparing the respective charges upon a pair of series connected capacitors comprising a pair of gaseous discharge devices having their cathodes connected in common and a terminal connection to a control element of each adapted to be detachably connected to one of the free terminals of the said capacitor pair, a load circuit for each said device connected between its anode and the common cathode connection, and an impedance connected between the said control elements having a center tap connected to the said common cathode connection, whereby a disparity in the charges upon the capacitors being compared produces a po tential in the said impedance to cause load current to flow in one of the said devices and to prevent load current from flowing in the other.

FRED C. HALLDEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,220,489 Lowkrantz Nov. 5, 1940 2,349,437 Keeler May 23, 194 2,416,625 Hooper Feb. 25, 1947 OTHER REFERENCES Dual-Triode Trigger Circuits, Phelps, Electronics, page 110, Fig. 1, July 1945.

Certificate of Correction Patent No. 2,514,054 July 4, 1950 FRED O. HALLDEN It is hereby certified that error appears in the printed Specification of the above numbered patent requiring correction as follows:

Column 13, line 33, for the Word cylindrically read cyclically;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Office. Signed and sealed this 10th day of October, A. D, 1950.

[SEAL] THOMAS F. MURPHY,

Assistant Commissioner of Patents.

Certificate of Correction Patent No. 2,514,054 July 4, 1950 FRED O. HALLDEN It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 13, line 33, for the Word cylindrically read cyclically;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Ofiice. Signed and sealed this 10th day of October, A. D, 1950,

THOMAS F. MURPHY,

Assistant Commissioner of Patents, 

